So-called “smartphones” are in widespread use. Examples of such devices include the famous iPhone® marketed by Apple Inc., and devices that are substantially similar in appearance to the iPhone and run the well-known Android® mobile operating system distributed by Google Inc. In addition to conventional mobile telephone functions, smartphones provide a wide array of computing functions in a form-factor that fits in a user's pocket or handbag. For some users, smartphones are a highly convenient tool and also an entertainment resource; for other users, the value of their smartphones goes beyond convenience or entertainment, with the devices serving as digital companions, helpers and focal points for numerous aspects of the users' business and/or personal lives.
Smartphones are not the only type of widely-used device with mobile communication capabilities. Many people also carry tablet computers, which in many ways resemble smartphones, but which provide added convenience and usefulness through larger touchscreen interfaces, more highly functional virtual keyboards, etc.
Both smartphones and tablet computers include rechargeable batteries, which are the power source for the devices, except for the usually limited periods of time when the devices may be plugged into an electrical power outlet via a charging device. For most users, because they rely on their smartphones and/or tablets in many ways, recharging the battery in those devices is a routine but highly important activity, and sometimes entails inconvenience or a sense of being in a predicament. The latter may occur when the user finds that the battery charge on the device is low, but he/she is unable to recharge the device because no power outlet is available, or the user is on the go, or the user has forgotten to carry the necessary charging device.
Published patent application WO2014006619 presents a proposal that could ameliorate potential mobile device charging inconvenience or predicaments in situations where no power outlet is available. According to this proposal, battery charge could be shared from one mobile device to another via a charging cable that connects the USB port of one device to the USB port of the other. One potential drawback of this proposal is that it still requires a user to have a suitable cable at hand if the charge sharing operation is to occur.